Firearm bolt stop



Jully 27, W43" G. HAMMOND FIREARM BOLT STOP Filed Aug. 26, 1941 Patented July 27, 1943 UNITED FIREARM BOLT 'sTor Grant Hammond, West Haven, Conn, assignor to Auto-Ordnance Corporation,

Bridgeport,

Conn, a. corporation of New York- Application August 26, 1941, Serial No. 408,286 3'Claims. (01. 42- 18) This invention relates to an improvement in automatic firearms of the type shown in my copending application Serial No. 405,971, filed August 8, 1941.

The object of this invention is to provide a firearm of the above-mentioned type wherein the bolt is held positively in the retracted position after the last cartridge is'fired and may be released by hand after the empty magazine has been replaced by a full magazine.

In one aspect the present invention involves a bolt stop movably mounted in the receiver of a firearm to move between an operative position in which it holds the bolt in retracted position after the last cartridge is fired and an inoperative position in which the bolt is free to reciprocate back and forth, the bolt stop being disposed in the receiver and the bolt having a groove along one side to accommodate the bolt stop when the latter is in inoperative position. In another aspect the invention involves a magazine having a fol-- lower for moving the cartridges in front of the bolt and an actuator for moving the bolt stop into operative position, together with a spring for moving the follower relatively to the magazine and movingthe actuator relatively to the follower. illustrative embodiment of the invention shown in the accompanying drawing, in which Fig. 1 is a side elevation of a firearm embodying this invention, apart of the magazine being broken away;

Fig. 2 is an enlarged sectional view taken along the line 22 in Fig. l with the magazine partly full;

Fig. 3 is a view similar to Fig. 2 of an empty magazine;

Fig. 4 is a left side view of the bolt, bolt stop and magazine with parts of the magazine broken away and the bolt in the advanced position; and

Fig. 5 is a view similar to Fig. 4 with the magaa zine empty and the bolt locked in the'retracted position. i l I The illustrated firearm comprises a stock S, a barrel BL, a trigger T, a receiver R, a bolt B, a bolt stop BS, 9. bolt actuator BA, and a magazine M.

The bolt 13 is cylindrical in contour and reciprocates back and forth in the receiver R. In its forward position (see Fig, 4) the bolt is over the magazine M. The magazine is mounted in an opening at the under side of the firearm and the bolt B is provided with recesses I8 which ac-- commodate the lips of the magazine. The bolt B is also provided with a recess l9 which accommo- Other aspects will be evident from the dates the bolt stop Be, as will be pointcdout below.

As shown in the drawing, the magazine is of I the box type, being provided with a springpressed follower 65 by which the uppermost cartridge is urged into position in front of the bolt when retracted. Near the upper end of the left side of the magazine is an opening ill and pivotally mounted on the bottom of the follower 66 by means of a pivot pin to is a bolt-stop actuator to having a nose It adapted to be projected through the opening 6'! when the magazine becomes empty. Normally the actuator 69 extends obliquely to the side walls of the magazine and the follower spring i l tends not only to lift the follower 66 but also to swing the actuator 68 about its pivot 68 so that its nose ll) passes through the opening e7 as the follower passes 1 above it.

The bolt stop BS comprises a thin elongate strip .pivotally mounted on the inner face of the left the actuator 89 when the magazine is empty.

The bolt stop is normally so positioned that it lies in the recess IQ of the bolt B and permits the free reciprocation thereof. When, however, the bolt stopBS is raised by the engagement of the nose It of the actuator 69 With the portion 13 (see Fig. 5), its rearward end 74 enters the path of the bolt and prevents forward movement of the bolt at the completion of its rec-oil movement. A handle 15 attached to the bolt stop and extending outwardly through a slot in the receiver R limits the downward movement of the bolt stop and permits its manual operation.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

I claim:

1. In a firearm having a receiver, a bolt reciprocable therein and a magazine by which cartridges are fed, a bolt stop, and an actuator carried by the magazine which aotuates the bolt stop when the magazine becomes empty, said magazine having an opening in its side adjacent the mouth of the magazine and including a follower on which the cartridges restand to the cartridges and by which the actuator is swung i tridge fed from the magazine.

ried by the magazine which actuates the bolt ii) which the follower is advanced to feed the car trid es and by which the actuator is swung on which the actuator is pivotally secured, and a spring by which the follower is advanced to feed on its pivot to cause the nose of the actuator to pass through said opening when the last car 2. In a firearm having a receiver, a bolt reciprocable therein i andia magazine bywhich cartridges are fed, a bolt stop, and an actuator carstop when the magazine becomes empty, said bolt stop being pivotally mounted upon said receiver adjacent themouth of the magazine, a follower in the magazine, said actuator being pivotally; mounted on the follower withinsaid magazine, i4 said magazine having an opening in the side wall thereof adjacent its mouthand beneath .said

bolt stop, and a spring within said magazine'by curegl anda spring, by which said follower is advanced; andsaid actuator swung on its pivot )to passthe: nose of the actuator through said opening into actuating engagement with said "boltstop.

GRANT HAMMOND.

-=der-faceof which said actuator is pivo ally se- 

